34 Microbial organisms are extremely important in regulating nematode populations like root-knot. The suppressive effect of a microbial bioagent is dependent on the strain, its density and virulence in the soil (Kamra and Rao 2013, Sellaperumal et al. 2014). Streptomyces spp. are gram positive filamentous bacteria that produce a wide array of biologically active compounds some of which are nematicidal (Chubachi et al. 1999, Takatsu et al. 2003). Many of them effectively colonize plant roots, influence plant growth and protect plant roots from pathogens. S. avermitilis produces nematicidal macrocyclic lactones such as avermectins sold under the tradename AVICTA by Syngenta (www.avicta.com). However, avicta is recommended for seed treatment and is currently registered for cotton in US. It moves from the treated seed alongside the growing root protecting the young plant from nematode parasitisation. Avermectin B1, also known as abamectin, is registered as an insecticide, acaricide and nematicide in more than 50 countries. Its liquid and granular formulations for control of plant parasitic nematodes, have been studied in wide range of crops such as tobacco, tomato (Garabedian and Van Gundy 1983), garlic (Roberts and Mathews 1995), banana (Jansson and Rabatin 1997, 1998), melon (Moreira and Barbosa 2002) and cotton (Faske and Starr 2006). It is 1 Indian Institute of Vegetable Research, Varanasi. 2 e mail: anjukamra@yahoo.com, Division of Nematology, 3 Centre for Environment Science and Climate Resilient Agriculture Indian Journal of Agricultural Sciences 86 (8): 998–1003, August 2016/Article Biological services by Streptomyces lavendulae MTCC 706 to control invasion, development and reproduction of root-knot nematode (Meloidogyne incognita) infecting tomato cv Pusa Ruby C SELLAPERUMAL 1 , ANJU KAMRA 2 and D K SHARMA 3 ICAR– Indian Agricultural Research Institute, New Delhi 110 012 Received: 16 April 2015; Accepted: 18 March 2016 ABSTRACT The drench application of S. lavendulae MTCC706 @ 2% v/w (SLT) resulted in less than 50% juvenile invasion of M. incognita J2s in tomato (cv. Pusa Ruby), delayed development of J4s, 50.7% reduction in root galling and 42.7% reduction in egg mass production, compared to control. The reproduction factor was 1.2 in SLT, compared to 2.4 in control in 45 days. SLT was compatible with the nematicide carbofuran, as increase in bioefficacy of SLT was observed with 60% reduction in root galling, 61.5% reduction in egg mass production, and a reproduction factor of 1.1 in the combined application with carbofuran @0.5 kg a.i/ha. Replanting of tomato in the pre-treated soil revealed a further reduction in root galling (81.3%), egg mass production (80.5%) and reproduction factor (0.6), indicating establishment of the actinomycete in the soil. Key words: Biological control, Meloidogyne incognita, Residual effect, Streptomyces lavendulae, Tomato known to inhibit egg hatching and paralyse juveniles (J2s) of M. arenaria but its persistence in the soil is low (Cayrol et al. 1993, Faske and Starr 2006). Limited investigations have been carried out on nematicidal potential of indigenous isolates of Streptomyces spp. in India (Jayakumar et al. 2005, Subhashini et al. 2009, Patidar et al. 2012). The present work on evaluation of antagonistic effects of this indigenous isolate of S. lavendulae MTCC 706, (isolated from compost sample) against M. incognita has not been reported so far, although Takatsu et al. (2003) have reported a nematocide from S. lavendulae isolate from Japan, SANK 64297 that caused inhibition of root galling on cucumber due to M. hapla at a MIC of 0.05 ppm. In the present study, the nematicidal effect of S. lavendulae MTCC 706 was significant on the nematode in laboratory bioassays, causing significant juvenile mortality and egg hatch inhibition (Perumal et al. 2014). Therefore, its bioefficacy as a drench treatment was evaluated in pot trials against root-knot nematode, M. incognita, infecting tomato cv Pusa Ruby. MATERIALS AND METHODS Root-knot nematode, Meloidogyne incognita collected from brinjal field of IARI, New Delhi was raised on brinjal var. Pusa purple long. Roots with conspicuous galls were washed gently with tap water. Females with egg masses were removed and kept individually in Syracuse cups half filled with water, stained in hot acid fuchsin-lactophenol